Question

Which of the following structure is not derived from external oblique muscle:

• A. Inguinal ligament
• B. Lacunar ligament
• C. Cooper ligament
• D. Linea Semilunaris

Answer 1

The Correct Option is D

Step 1: Group the three ligaments. Trace the lower edge of the external oblique aponeurosis: it rolls under to make the inguinal ligament, sends a fan medially to make the lacunar ligament, and continues laterally along the pubic pecten as the pectineal (Cooper) ligament. All three are continuations of one sheet of external oblique aponeurosis. Step 2: Now consider the linea semilunaris. This is a vertical tendinous crease at the lateral margin of the rectus abdominis, marking where the combined aponeuroses of external oblique, internal oblique and transversus abdominis fuse to enclose the rectus. Step 3: Because it depends on all three flat muscles rather than the external oblique by itself, the linea semilunaris stands apart from the ligament trio. Step 4: Therefore the odd one out, not derived from the external oblique, is the linea semilunaris. \[\boxed{\text{Linea Semilunaris}}\]